[MIPS] Define MIPS_CPU_IRQ_BASE in generic header

The irq_base for {mips,rm7k,rm9k}_cpu_irq_init() are constant on all
platforms and are same value on most platforms (0 or 16, depends on
CONFIG_I8259).  Define them in asm-mips/mach-generic/irq.h and make
them customizable.  This will save a few cycle on each CPU interrupt.

A good side effect is removing some dependencies to MALTA in generic
SMTC code.

Although MIPS_CPU_IRQ_BASE is customizable, this patch changes irq
mappings on DDB5477, EMMA2RH and MIPS_SIM, since really customizing
them might cause some header dependency problem and there seems no
good reason to customize it.  So currently only VR41XX is using custom
MIPS_CPU_IRQ_BASE value, which is 0 regardless of CONFIG_I8259.

Testing this patch on those platforms is greatly appreciated.  Thank
you.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 3 insertions, 1 deletions

diff --git a/include/asm-mips/mach-cobalt/cobalt.h b/include/asm-mips/mach-cobalt/cobalt.h
index 00b0fc68d5cb..24a8d51a55a3 100644
--- a/include/asm-mips/mach-cobalt/cobalt.h
+++ b/include/asm-mips/mach-cobalt/cobalt.h
@@ -12,6 +12,8 @@
 #ifndef __ASM_COBALT_H
 #define __ASM_COBALT_H
 
+#include <irq.h>
+
 /*
  * i8259 legacy interrupts used on Cobalt:
  *
@@ -25,7 +27,7 @@
 /*
  * CPU IRQs  are 16 ... 23
  */
-#define COBALT_CPU_IRQ          16
+#define COBALT_CPU_IRQ          MIPS_CPU_IRQ_BASE
 
 #define COBALT_GALILEO_IRQ      (COBALT_CPU_IRQ + 2)
 #define COBALT_SCC_IRQ          (COBALT_CPU_IRQ + 3)    /* pre-production has 85C30 */